Reaction of dimethyl acetylenedicarboxylate with derivatives of malonic acid: pentamethoxycarbonylcyclopentadienide anion, tetramethoxy-carbonylcyclopentadienone, cyanotetramethoxyfulvenolate anion, and related compounds

@inproceedings{Cookson1967ReactionOD,
  title={Reaction of dimethyl acetylenedicarboxylate with derivatives of malonic acid: pentamethoxycarbonylcyclopentadienide anion, tetramethoxy-carbonylcyclopentadienone, cyanotetramethoxyfulvenolate anion, and related compounds},
  author={Richard C. Cookson and J. B. Henstock and John Craig Hudec and B. R. D. Whitear},
  year={1967}
}
The revised formulation of the adducts of dimethyl malonate with dimethyl acetylenedicarboxylate in the presence of pyridine and acetic acid as tautomeric octamethyl cycloheptadienoctacarboxylates [(III) and (IV)] is confirmed. Both tautomers, or the analogues from other esters of malonic acid, are converted by potassium acetate into Diels' potassium pentamethoxycarbonylcyclopentadienide (VIa). Diazomethane methylates the free cyclo-pentadiene, which is a very strong acid, to the C-methyl… CONTINUE READING